Cell C refusing to cancel my contract !!!!

OMG!! Cell C service is so poor!!!! I have cancelled my month to month contract with Cell C on the 20th September 2022 as I was busy relocating to CPT. I received a call from them to confirm the cancellation which I agreed. I have send numerous emails contacted them on numerous occasions to cancel my contract and to date still nothing. Since the month of September I am struggling to cancel as they refusing to cancel and have been sending me Billing statement which I continually respond on with the "proof of emails" requesting to cancel my contract. I don't know what to do anymore its ridiculous.